DE102017203541B3 - Drive device and motor vehicle with a drive device - Google Patents

Abstract

The invention relates to a drive device (10) for a motor vehicle (100), with at least one drive machine (20) and with at least one gearbox (40). The drive device (10) has at least one cooling system (12), which is designed to act on the at least one drive machine (20) and the at least one gearbox (40) at least in regions with a cooling medium (14). Another aspect of the invention relates to a motor vehicle (100) with a drive device (10).

Description

The invention relates to a drive device for a motor vehicle, with at least one drive machine and with at least one manual transmission. The manual transmission can be configured, for example, as an automatic transmission or as a manual transmission. Another aspect of the invention relates to a motor vehicle with such a drive device.

From the US 2,796,239 A is a drive device with an internal combustion engine and a transmission known. A cooling jacket of the internal combustion engine is connected via pipes to a housing of the manual transmission, whereby cooling water can be exchanged between the housing and the cooling jacket.

The DE 10 2015 213 109 A1 discloses a torque transmitting device with a planetary gear. The planetary gear has planet gears, a first ring gear and / or a first sun gear and a second ring gear and / or a second sun gear. The first planet gear meshes with the first ring gear and / or the first sun gear and the second planet gear meshes with the second ring gear and / or the second sun gear. Further, the first and the second planetary gear are axially spaced from each other on a planetary shaft and in each case rotatably connected thereto or rotatably connected, wherein the planetary shaft is mounted such that the planetary gears are fixed in one position. The planetary gear further includes a dual clutch device, which may be configured as a dry or wet executed dual clutch device.

The DE 10 2014 201 254 A1 discloses a transmission assembly and a powertrain for a hybrid vehicle and a corresponding hybrid vehicle. The gear arrangement comprises an electric machine connected to an input shaft, an internal combustion engine input shaft that can be connected to an internal combustion engine, an output shaft, and a Ravigneaux planetary gearset, whose web can be fixed to a transmission housing by means of a brake. The gear arrangement is characterized by a switchable clutch arrangement, by means of which the web and a second sun of the Ravigneaux planetary gear set as well as the internal combustion engine input shaft are selectively coupled with each other to transmit torque. Furthermore, the gear arrangement has an auxiliary shaft which passes through the gear arrangement as a coaxial central shaft in their length. The auxiliary shaft is on the one hand with the brake and on the other hand with the switchable coupling arrangement in interaction.

Such brakes are particularly thermally stressed during braking of transmission elements, so for example by transmission shafts.

Object of the present invention is to provide a drive device and a motor vehicle of the type mentioned, which can be cooled under a very low cost. This object is achieved by a drive device with the features of claim 1, as well as by a motor vehicle according to claim 8. Advantageous developments of the invention are given by the dependent claims.

The invention is based on a drive device for a motor vehicle with at least one drive machine and with at least one manual transmission. The prime mover may preferably be an e-machine. The gearbox is used to translate driving torque by which the motor vehicle can be driven. By means of the gearbox so different ratios can be adjusted. In other words, can be switched in the transmission between different gears.

In addition, the drive device has at least one cooling system, which is designed to act on the at least one drive machine and the at least one gearbox at least partially with a cooling medium. By means of the cooling system so cooling of both the prime mover and the gearbox is possible, which no separate cooling devices must be provided for the prime mover and the transmission and accordingly cooling can be done with very little effort. The cooling system may, for example, at least one heat exchanger for dissipating heat to the environment, a plurality of cooling channels, which extend at least partially through the drive machine and the gearbox, and at least one pump for conveying the cooling medium through the cooling channels. The cooling channels may be formed, for example, as annular channels and extend over respective housing portions of the drive machine and the gearbox. A particular advantage is that can be dispensed by the cooling of the gearbox by means of the cooling system at least partially on a cooling of transmission components by transmission oil contained in the transmission, whereby any churning losses can be reduced.

The term "applying" is in the context of the invention, a moistening and thus a wetting or flowing through the Gearbox and the prime mover to understand the cooling medium.

Furthermore, the cooling system comprises at least one transmission cooling channel arrangement, which extends at least partially through a gear housing of the gearbox and at least one engine cooling channel arrangement, which extends at least partially through a machine housing of the drive machine. This is advantageous since a particularly needs-based cooling is made possible by such cooling channel arrangements in the transmission housing or engine housing. The transmission cooling channel arrangement or the machine cooling channel arrangement can comprise respective cooling channels which can extend both in the axial extension direction of the transmission housing or of the machine housing and in the circumferential direction of the transmission housing or of the machine housing. This allows a particularly uniform, at least partially cooling of the gearbox or the drive machine.

The transmission cooling duct arrangement and the engine cooling duct arrangement can be connected to form a closed cooling circuit. For this purpose, the machine cooling channel arrangement can have, for example, overflow channels, via which the machine cooling channel arrangement can be fluidically connected to the transmission cooling channel arrangement. As a result, cooling of the gearbox and the engine is made possible with very little effort, since only one pump is sufficient to promote the cooling medium through both the Getriebekühlkanalanordnung and by the machine cooling channel arrangement. The pump may for example be integrated in the prime mover. The pump and the machine cooling channel arrangement allow autonomous cooling of the drive machine by the cooling medium is moved relative to the machine housing, while being promoted, for example, in the circumferential direction. Due to the connection between the engine cooling channel arrangement and the transmission cooling channel arrangement, the cooling medium is conveyed during operation of the pump both by the drive machine and by the gearbox so as to cool the transmission as well as the transmission.

According to the invention, the gearbox has at least one switching unit for adjusting at least one transmission ratio of the gearbox, wherein the at least one switching unit is at least partially contact heat conductive coupled to the transmission cooling duct arrangement and / or coupled. This is advantageous because a direct contact of the switching unit with the cooling medium is prevented by a contact heat pipe and thus, for example, splashing of the switching unit in the cooling medium can be avoided. The switching unit can be partially engaged with the transmission housing, whereby accordingly the switching unit is also partially contact heat-conducting coupled to the transmission cooling channel arrangement. A heat transfer can then take place, for example, by means of a cooling channel wall separating the transmission cooling channel arrangement from the switching unit. The cooling channel wall may be part of the transmission housing of the gearbox. In addition or as an alternative, the switching unit can also be coupled with the transmission cooling channel arrangement at least in regions in a contact-heat-conducting manner. This is for example the case when the switching unit is in an activated state in contact with the transmission housing, but in a deactivated state, an air gap between the switching unit and the transmission housing may be present. The switching unit can be completely accommodated in a housing interior bounded by the gearbox housing relative to an environment of the gearbox.

In an advantageous development of the invention, the transmission cooling channel arrangement has at least two cooling channel openings, by means of which the transmission cooling channel arrangement is fluidically coupled to the machine cooling channel arrangement. This is advantageous because by means of the at least two cooling channel openings both a media inlet and thus an inflow, as well as a media outlet and thus an outflow of the cooling medium from the machine cooling channel arrangement in the transmission cooling channel arrangement or from the transmission cooling channel arrangement in the machine cooling channel arrangement is made possible.

In a further advantageous development of the invention, the at least one switching unit has at least one switching element, which is accommodated at least in regions in a recess of the transmission housing and is coupled to the transmission cooling channel arrangement in a contact-heat-conducting manner. This is advantageous because the arrangement in the recess enables a particularly large-area contact between the switching element and the transmission housing and thus a particularly efficient heat conduction between the switching unit or its switching element and the transmission cooling channel arrangement. The switching element may for example be formed as a disc which can be positively connected to a transmission shaft (inner disc) or the transmission housing (outer pane).

In a further advantageous development of the invention, the at least one switching unit is designed as a brake, in particular as a dry brake. This is advantageous since, by means of such a brake, a particularly delay-free shifting between different gear ratios is made possible. Is the brake as dry Brake, which may also be referred to as a dry brake, formed, so this can be operated without cooling by transmission oil, which any churning losses can be avoided. Dry brakes are also designed much less expensive than so-called wet brakes, which are cooled under the action of transmission oil and accordingly can be operated due to planishing effects compared to dry brakes under correspondingly higher losses. The cooling system allows an increase in the life of the dry brake, for example, friction pads of the dry brake are less prone to wear due to the cooling by means of the cooling system. Due to the cooling by means of the cooling system, the brake can be designed to be particularly small and compact overall, since the cooling an overall lower thermal load of the brake occurs during their operation. If the brake is designed as a dry brake, so hydraulic measures for lubrication and cooling of the brake can be omitted, whereby a total of less gear oil must be carried in the manual transmission.

In a further advantageous embodiment of the invention, the transmission comprises the drive machine. In other words, therefore, the prime mover may be part of the gearbox. This is of particular advantage, since thus by the transmission and the prime mover, for example, a start of the motor vehicle from the state is possible, without having to resort to other drive motors, such as an internal combustion engine of the motor vehicle. The drive machine can be accommodated in a housing interior of the gearbox and thus be delimited by the gearbox of the gearbox from an environment of the gearbox.

In a further advantageous development, the drive machine is coupled torque-transmitting with at least one transmission element of the gearbox. This is advantageous because it provides additional degrees of freedom in the setting of possible gear ratios of the gearbox. The at least one transmission element may be different from a transmission input shaft and a transmission output shaft of the gearbox. The prime mover may have a drive shaft, which may be coupled to the at least one transmission element. For this purpose, for example, a drive pinion connected to the drive shaft of the drive machine can be in engagement with the gear element designed as a gearwheel, for example.

In a further advantageous embodiment of the invention, the prime mover is an electric machine. This is advantageous because a particularly high drive torque can be provided by the electric machine even when the drive shaft of the electric machine is stationary. The prime mover can be operated as an electric motor and as a generator to enable a recuperation of energy.

Another aspect of the invention relates to a motor vehicle with a drive device according to the invention. In such a motor vehicle, cooling is possible with particularly little effort, since both the drive machine and the gearbox can be cooled by means of the cooling system. The features presented in connection with the drive device according to the invention and their advantages apply correspondingly to the motor vehicle according to the invention and vice versa.

The invention also includes developments of the motor vehicle according to the invention, which have features as they have already been described in connection with the developments of the drive device according to the invention. For this reason, the corresponding developments of the motor vehicle according to the invention are not described again here.

In the following, embodiments of the invention are described. For this purpose, the only Fig. Shows a half section of a portion of a drive device, which is arranged in a motor vehicle.

The exemplary embodiments explained below are preferred embodiments of the invention. In the exemplary embodiments, the described components of the embodiments each represent individual features of the invention, which are to be considered independently of one another, which each further develop the invention independently of one another and thus also individually or in a different combination than the one shown as part of the invention. Furthermore, the described embodiments can also be supplemented by further features of the invention already described.

In the figures, functionally identical elements are each provided with the same reference numerals.

The figure shows a schematically illustrated motor vehicle 100 with a drive device 10 , From the drive device 10 In the present case, only a partial area is shown and shown in a sectional view.

The drive device 10 has a prime mover 20 and a manual transmission 40 on. The prime mover 20 is in the manual transmission 40 integrated. In other words, the manual transmission includes 40 the prime mover 20 , The prime mover 20 is present torque transmitting with a translation element 38 of the gearbox 40 coupled. The translation element 38 can, as shown here, for example, a gear of the gearbox 40 correspond and accordingly of a transmission input shaft and a transmission output shaft (not shown here) of the gearbox 40 to be different. The prime mover 20 is presently designed as an electric machine and made possible by the torque-transmitting coupling with the transmission element 38 a start and thus a moving of the motor vehicle 100 out of its stagnation. Further drive motors, so for example a not shown here internal combustion engine of the motor vehicle 100 , can thus during startup of the motor vehicle 100 by means of the prime mover 20 remain switched off (deactivated). The prime mover 20 can, as shown in the present case, a drive shaft 24 comprising, mediated by a drive pinion 26 with the translation element 38 can be engaged.

The drive device 10 has a cooling system 12 on, which is adapted to the prime mover 20 and the manual transmission 40 partially with a cooling medium 14 to act on. The cooling medium 14 may be water or, for example, cooling water (water-glycol mixture). For cooling, the cooling system 12 a heat exchanger not shown here, which may also be referred to as a heat exchanger have. To the cooling medium 14 To promote the cooling system 12 Have a pump, which is also not shown in the present case.

The cooling system 12 has a transmission cooling channel arrangement 50 on, which at least partially by a transmission housing 42 of the gearbox 40 extends. Furthermore, the cooling system 12 a machine cooling channel arrangement 30 on, which at least partially by a machine housing 22 the prime mover 20 extends. The engine cooling channel arrangement 30 can at least one machine cooling channel 32 which, for example, spirally in the circumferential direction of the machine housing 22 and can extend into this. The transmission cooling duct arrangement 50 has in this case two cooling channel openings 52 . 54 on, by means of which the transmission cooling duct arrangement 50 fluidic with the machine cooling channel arrangement 30 is coupled. For this purpose, the machine cooling channel arrangement 30 a first overflow channel 34 and a second overflow channel 36 on. The first overflow channel 34 is in the present embodiment with the first cooling channel opening 52 connected fluid-conducting, whereas the second overflow 36 with the second cooling channel opening 54 fluidly connected.

The first cooling channel opening 52 is designed as an inflow over which an indicated by an arrow media entry 16 of the cooling medium 14 from the engine cooling passage arrangement 30 in the transmission cooling duct arrangement 50 can be done. The second cooling channel opening 54 In the present case, it is designed as a drain, via which a medium also illustrated by an arrow emerges 18 from the transmission cooling duct arrangement 50 in the machine cooling channel arrangement 30 can be done.

The machine housing 22 is with the gearbox 42 connected to a common contact area. At the contact area is at least one media seal 94 provided, which is a leakage of the cooling medium 14 prevented to the environment.

The manual transmission 40 has at least one switching unit 44 for adjusting at least one transmission ratio of the gearbox 40 on. The switching unit 44 is presently designed as a dry brake and contact heat-conducting with a with the first cooling channel opening 52 coupled radial cooling channel 56 and one with the second cooling channel opening 54 fluidically coupled radial cooling channel 58 coupled. The two radial cooling channels 56 . 58 lead the cooling medium 14 at least partially in the circumferential direction about the switching unit 44 around, causing the switching unit 44 in the radial extension direction through the cooling medium 14 , in particular by heat transfer in the form of heat conduction, is cooled. The heat conduction takes place here via a cooling duct wall 51 in a (housing-fixed) outer support of the transmission housing 42 , on which a middle disc 47 and an outer pane 49 the switching unit 44 interlock positively. The transmission cooling duct arrangement 50 also extends over a housing section 41 of the gearbox 42 in which an axial cooling channel 60 for cooling the switching unit 44 in the housing section 41 is provided. The axial cooling channel 60 has, as can be seen in the sectional view, an L-shaped circumferential (rotational) cross-section, is fluidic with at least one of the radial cooling channels 56 . 58 connected (not shown here) and leads the cooling medium 14 at least partially in the axial direction of extension of the switching unit 44 at a distance to an inner pane 46 the switching unit 44 at least partially along this. The axial cooling channel 60 is preferably in the radial direction of extension of the switching unit 44 at the height of the first inner pane 46 and at least partially in the housing section 41 arranged circumferentially. This is a particularly targeted cooling of in the Radial extension direction at the height of the first inner pane 46 arranged (not designated here) friction linings of the switching unit 44 given.

The switching unit 44 (Brake) includes next to the first inner pane 46 also a second inner pane 48 , The inner windows 46 . 48 are present with a transmission shaft 80 of the gearbox 40 engaged. The transmission shaft 80 is about respective shaft bearings 82 on the gearbox 42 stored. To the gear shaft 80 opposite the gearbox 42 support and thus a relative rotation of the gear shaft 80 to the transmission housing 42 To prevent, a hydraulically movable actuating piston 90 is provided, by means of which the switching unit 44 can be activated and deactivated. The actuating piston 90 is about a piston seal 92 sealing in the transmission housing 42 added.

In the activated state, the actuating piston exercises 90 a contact pressure on the discs 46 . 47 . 48 . 49 out, resulting in between the middle disk 47 , the outer pane 49 and the inner windows 46 . 48 a frictional connection to the respective friction linings arises and the transmission shaft 80 on the gearbox 42 held and thus supported. Due to the contact force, the inner pane 46 which also serves as a switching element of the switching unit 44 can be referred to the housing section 41 pressed, creating a contact heat pipe between the Axialkühlkanal 60 and the inner pane 46 he follows. The contact heat conduction takes place by mediation of a wall 72 of the housing section 41 , The wall 72 separates the axial cooling channel 60 from the inner pane 46 (Switching element). Is the switching unit 44 in its deactivated state, in which the actuating piston 90 no pressure on the discs 46 . 47 . 48 . 49 exerts a contact heat conduction between the transmission cooling channel arrangement 50 or the axial cooling channel 60 and the inner pane 46 be prevented. In the housing section 41 can also be a recess 70 be provided, in which the inner pane 46 (Switching element) received and thereby kontaktwärmeleit with the Axialkühlkanal 60 the transmission cooling duct arrangement 50 can be coupled. The recess 70 allows a particularly efficient cooling of the inner pane 46 , This is made possible by the recess 70 the inner pane 46 partially surrounds when the actuating piston 90 (when activating the switching unit 44 ) the disks 46 . 47 . 48 . 49 pressed against each other while the inner pane 46 into the recess 70 and to the wall 72 pressed.

Overall, the examples, such as by the present invention, an effective cooling for dry brakes of the gearbox 40 , which may be formed for example as an automatic transmission, is possible. The performance of the dry, housing-fixed switching elements (discs 47 . 49 ) can by active cooling by means of the cooling system 12 be optimized. This allows the existing potentials of the manual transmission 40 which is the prime mover 20 can be used particularly effectively. Cooling by means of the cooling system 12 allows an expansion of additional space in the manual transmission 40 by implementing compact designs of the switching elements (discs 46 . 47 . 48 . 49 ). Due to the active cooling of the gearbox housing 42 fixed discs (slices 47 . 49 ) can the load capacity (torque capacity) of the entire switching unit 44 be increased significantly, as one for the materials and respective discs 46 . 47 . 48 . 49 tolerable operating temperature, which at a relative movement between the discs 46 . 47 . 48 . 49 arises as a result of exerting the contact pressure, can be lowered. This operating temperature, which in the frictional connection of the individual discs 46 . 47 . 48 . 49 occurs, represents a critical design size for the switching unit 44 By effectively lowering the operating temperature by means of the cooling system 12 Accordingly, a design of the switching unit 44 be positively influenced so that the switching unit 44 can be made very compact. For example, the respective friction linings can be made smaller than without cooling by the cooling system 12 it is possible.

Furthermore, by means of the active cooling by the cooling system 12 a temperature radiation from the switching unit 44 be reduced to adjacent transmission components.

The switching unit 44 may, as shown herein, generally be configured as a multi-slice dry brake or as a single-slice dry brake.

While usually known in the prior art automatic transmissions wet multi-plate clutches and wet brakes are used to allow a frictional connection of transmission components, can by the present invention to dry switching units for switching respective gears of the gearbox 40 , So to set different ratios, be resorted to. In clutches generally run the individual coupling elements with respective connected to the clutches gear shafts, whereas in braking individual brake elements are arranged fixed to the housing. In known from the prior art transmissions the clutches or brakes are oil-washed, which is urgently required for their function and the cooling of the friction linings in wet clutches and wet brakes.

The invention generally enables the use of dry brakes in the manual transmission 40 , as the operating temperature of the dry brake (switching unit 44 ) by means of the cooling system 12 can be effectively lowered. The cooling system 12 allows cooling of respective friction contact points in the region of the friction linings between the individual discs 46 . 47 . 48 . 49 or the components of the switching unit involved in the temperature generation of the operating temperature 44 through the cooling medium 14 ,

The manual transmission 40 can be configured as an electrified transmission by the prime mover 20 designed as an electric machine and in the manual transmission 40 is integrated. The engine cooling channel arrangement 30 can be attached to a housing-fixed stator of the electric machine (drive machine 20 ), wherein the engine cooling passage arrangement 30 water-flowed annular channels in an outer region of a stator or a cooling jacket of the drive machine 20 can have. The cooling medium 14 may be water or a water-glycol mixture, to name just a few examples.

The present invention enables a common cooling of the prime mover 20 and at least the one with the gearbox 42 engaged discs 47 . 49 the switching unit 44 , The engine cooling channel arrangement 30 and the transmission cooling passage arrangement 50 In general, similar annular channels for guiding the cooling medium 14 which are in the transmission housing 42 or in the machine housing 22 can be admitted.

Claims (8)

Drive device (10) for a motor vehicle (100) with at least one drive machine (20) and with at least one gearbox (40), wherein the drive device (10) has at least one cooling system (12) which is adapted to drive the at least one drive machine (10). 20) and the at least one gearbox (40) at least partially act upon a cooling medium (14), wherein the cooling system (12) at least one transmission cooling channel arrangement (50) extending at least partially through a transmission housing (42) of the gearbox (40) , and at least one machine cooling channel arrangement (30), which extends at least partially through a machine housing (22) of the drive machine (20), characterized in that the gearbox (40) at least one switching unit (44) for setting at least one transmission ratio of the gearbox ( 40), wherein the at least one switching unit (44) at least bere For example, contact heat-conducting with the transmission cooling channel arrangement (50) can be coupled and / or coupled. Drive device (10) after Claim 1 , characterized in that the transmission cooling channel arrangement (50) has at least two cooling channel openings (52, 54), by means of which the transmission cooling channel arrangement (50) is fluidically coupled to the machine cooling channel arrangement (30). Drive device (10) after Claim 1 or 2 , characterized in that the at least one switching unit (44) has at least one switching element (46) which is at least partially received in a recess (70) of the transmission housing (42) and contact heat-conducting coupled to the transmission cooling channel arrangement (50). Drive device (10) according to one of the preceding claims, characterized in that the at least one switching unit (44) as a brake, in particular as a dry brake, is formed. Drive device (10) according to one of the preceding claims, characterized in that the gearbox (40) comprises the drive machine (20). Drive device (10) according to one of the preceding claims, characterized in that the drive machine (20) is coupled to transmit torque with at least one transmission element (38) of the gearbox (40). Drive device (10) according to one of the preceding claims, characterized in that the drive machine (20) is an electrical machine. Motor vehicle (100) with a drive device (10) according to one of the preceding claims.

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